打印进程内存信息

用gdb调试程序时，如果想查看进程的内存映射信息，可以使用“i proc mappings”命令（i是info命令缩写），例如:

(gdb) i proc mappings
process 27676 flags:
PR_STOPPED Process (LWP) is stopped
PR_ISTOP Stopped on an event of interest
PR_RLC Run-on-last-close is in effect
PR_MSACCT Microstate accounting enabled
PR_PCOMPAT Micro-state accounting inherited on fork
PR_FAULTED : Incurred a traced hardware fault FLTBPT: Breakpoint trap

Mapped address spaces:

    Start Addr   End Addr       Size     Offset   Flags
     0x8046000  0x8047fff     0x2000 0xfffff000 -s--rwx
     0x8050000  0x8050fff     0x1000          0 ----r-x
     0x8060000  0x8060fff     0x1000          0 ----rwx
    0xfee40000 0xfef4efff   0x10f000          0 ----r-x
    0xfef50000 0xfef55fff     0x6000          0 ----rwx
    0xfef5f000 0xfef66fff     0x8000   0x10f000 ----rwx
    0xfef67000 0xfef68fff     0x2000          0 ----rwx
    0xfef70000 0xfef70fff     0x1000          0 ----rwx
    0xfef80000 0xfef80fff     0x1000          0 ---sr--
    0xfef90000 0xfef90fff     0x1000          0 ----rw-
    0xfefa0000 0xfefa0fff     0x1000          0 ----rw-
    0xfefb0000 0xfefb0fff     0x1000          0 ----rwx
    0xfefc0000 0xfefeafff    0x2b000          0 ----r-x
    0xfeff0000 0xfeff0fff     0x1000          0 ----rwx
    0xfeffb000 0xfeffcfff     0x2000    0x2b000 ----rwx
    0xfeffd000 0xfeffdfff     0x1000          0 ----rwx

首先输出了进程的flags，接着是进程的内存映射信息。
参见 gdb手册.

此外，也可以用"i files"（还有一个同样作用的命令：“i target”）命令，它可以更详细地输出进程的内存信息，包括引用的动态链接库等等，例如：

(gdb) i files
Symbols from "/data1/nan/a".
Unix /proc child process:
    Using the running image of child Thread 1 (LWP 1) via /proc.
    While running this, GDB does not access memory from...
Local exec file:
    `/data1/nan/a', file type elf32-i386-sol2.
    Entry point: 0x8050950
    0x080500f4 - 0x08050105 is .interp
    0x08050108 - 0x08050114 is .eh_frame_hdr
    0x08050114 - 0x08050218 is .hash
    0x08050218 - 0x08050418 is .dynsym
    0x08050418 - 0x080507e6 is .dynstr
    0x080507e8 - 0x08050818 is .SUNW_version
    0x08050818 - 0x08050858 is .SUNW_versym
    0x08050858 - 0x08050890 is .SUNW_reloc
    0x08050890 - 0x080508c8 is .rel.plt
    0x080508c8 - 0x08050948 is .plt
    ......
    0xfef5fb58 - 0xfef5fc48 is .dynamic in /usr/lib/libc.so.1
    0xfef5fc80 - 0xfef650e2 is .data in /usr/lib/libc.so.1
    0xfef650e2 - 0xfef650e2 is .bssf in /usr/lib/libc.so.1
    0xfef650e8 - 0xfef65be0 is .picdata in /usr/lib/libc.so.1
    0xfef65be0 - 0xfef666a7 is .data1 in /usr/lib/libc.so.1
    0xfef666a8 - 0xfef680dc is .bss in /usr/lib/libc.so.1

参见 gdb手册